Bug Fix: Respect CMake output directory overrides

[dragoiuc]

Fixes #4957.

This PR updates GoogleTest's CMake output directory handling so that user-provided
CMAKE_<ARTIFACT>_OUTPUT_DIRECTORY values are respected.

Before this change, cxx_library_with_type set the output directory properties
directly on each target. Because of that, setting something like
CMAKE_ARCHIVE_OUTPUT_DIRECTORY would not affect where libgtest.a or
libgtest_main.a were placed.

The fix keeps GoogleTest's existing default layout when users do not set any
custom output directories, but avoids overriding the user's values when they do.

I also added a regression test for this behavior. The test checks that:

• default builds still place artifacts in the expected bin/ and lib/ locations
• custom CMAKE_*_OUTPUT_DIRECTORY values are respected

Tests run:

• cmake -S . -B /tmp/gtest-pr-check -DBUILD_GMOCK=OFF -Dgtest_build_tests=ON -DINSTALL_GTEST=OFF
• cmake --build /tmp/gtest-pr-check -j2
• ctest --test-dir /tmp/gtest-pr-check -R googletest-cmake-output-directory-test --output-on-failure
• ctest --test-dir /tmp/gtest-pr-check --output-on-failure
• manual smoke check with a custom CMAKE_ARCHIVE_OUTPUT_DIRECTORY for gtest and gtest_main